This app execution is fantastic. Compared to the classic Facebook app, Camera runs smoothly, loads fast, has intuitive use, and feels native. But why would Facebook release a separate camera app? Don’t they already own Instagram?

The answer lies in Facebook’s secret sauce to engagement - photos. The entire engine of Facebook runs on users taking, tagging, liking, and commenting on photos. Without it, Facebook is nothing. And if you take a close look, you’ll see that the entire Camera app is designed to get you to post as many photos as possible.

They have camera roll integration, allowing me to quickly pick a photo to upload.

Their story post form includes an extra call to action to add more photos.

They used a batch-style picker that lets me upload lots of photos to Facebook at once.

Also, using some nefarious device-based tracking, Camera knows exactly who I am, as soon as I’ve installed it.

And if it wasn’t already obvious, Facebook clearly wants to be a replacement for the default Camera app.

This all makes complete sense for Facebook. They know that active user numbers for the desktop website are drying up. They also know that those people are moving to mobile. If Facebook plans to survive, they need to make sure their primary viral channel makes it on to mobile as well. They need to do whatever they can to get more users taking more photos.